Retractable guard cam for pattern wheel knitting apparatus

ABSTRACT

A retractable guard cam is provided at each of the pattern wheel feed stations of a circular knitting machine. Such retractable guard cam, which prevents the uncontrolled flight of needles from a raise cam, is located on the radially inward side of each cam section block including a pattern wheel, but can be retracted from the radially outward side of the block to a position permitting needles to be raised without interference from the cam.

United States Patent [72] Inventor Harry Agulnek Brooklyn, .\.Y.

[21] Appl. No. 832,564

[22] Filed June 12,1969

[45] Patented July 27,1971

[73] Assignee The Singer Company New York. NX.

[54] RETRACTABLE GUARD CAM FOR PATTERN WHEEL KNITTING APPARATUS 5Claims,6 Drawing Figs.

[52) US. Cl 66/50 A, 66/57 [51] Int. Cl D04b 15/76 [50] Field of Search66/50, 50 A, 50 8,40, 36 B, 25, 57, 78. 38

[56] References Cited UNITED STATES PATENTS 3,513,666 5/1970 Mishcon1,181,520 5/1916 Glenn 66/38 1.278634 9/1918 Glenn t t t. 66/382,068,179 l/l937 Hon-rocks; 66/50 3,457,736 7/1969 Mishcon 66/50 AFOREIGN PATENTS 17,350 1904 Great Britain 66/50 1,529 11/1889Switzerland 66/78 Primary Examiner- Wm. Carter ReynoldsAttorneys-Marshall J Breen, Chester A. Williams, Jr. and

William V. Ebs

ABSTRACT: A retractable guard cam is provided at each of the patternwheel feed stations of a circular knitting machine. Such retractableguard cam, which prevents the uncontrolled flight of needles from araise cam, is located on the radially inward side of each cam sectionblock including a pattern wheel, but can be retracted from the radiallyoutward side of the block to a position permitting needles to be raisedwithout interference from the cam.

PATENTFUJZJLZYIQH 8,595,033

SHEET 1 OF 2 INVENTOR. g 3 8y H urry Agulnek WITNESS= ATTORNEY IRETRACTABLE GUARD CAM F ORPATTERN WHEEL KNITTING APPARATUSCROSS-REFERENCE TO RELATED APPLICATIONS The present application isdirected to an invention which is an improvement upon the invention ofcopending application Ser. No. 670,097 filed Sept. 25, 1967 and issuedas U.S. Pat. No. 3,513,666 on May 26,1970.

BACKGROUND OF THE INVENTION 1. Field of the Invention The inventionrelates to circular equipped with pattern wheels.

2. Description ofthe Prior Art In high speed circular knitting machineof the type shown for example in copending U.S. Pat. application Ser.No. 670,097, wherein one of the butts of two-butt needles cooperateswith raise, placer and stitch cams and the other butt cooperates withpattern wheels, a guard cam is provided at each of the cam sections.Such guard cam includes two portions one of which is above the raise camand is subject IO en gagement by said one butt whereby the uncontrolledupward flight of needles from the raise cams may be prevented. The otherportion of the guard cam is above the placer cam and is engageable withsaid one butt and is effective to prevent the needles from assumingpositions in which they may miss the stitch cam or be damaged byengagement with the upper end of such cam. In the machine of said U.S.Pat. application Ser. No. 670,097, the guard cams are fixedly secured tothe section blocks, and because of their fixed positions it is difficultto time the pattern wheels when they are mounted on the machine. Alsowith the guard cams in fixed positions in such machine, damaged needlescannot be withdrawn from the cylinder of the machine at any of the camsections unless the cam section is first removed.

knitting machines SUMMARY OF THE INVENTION In accordance with thisinvention a retractable guard cam, located above a raise and placer cam,is provided for machines of the type disclosed in said U.S. Pat.application Ser. No. 670,097, at each of the cam sections including apattern wheel. The guard cam is rendered movable between a normaloperative position in which the cam is engageable by one butt ofmultibutt needles and another position which is radially outward fromthe normal operative position and in which the needles may be raisedwithout the said one needle butt engaging the cam. With the guard camretractable as described herein, timing of the pattern wheels and thereplacement of damaged needles is greatly facilitated.

It is an object of the invention to facilitate, in a circular knittingmachine having raise and placer cams in association with guard cams andpattern wheels, and multibutt needles with one butt engageable with camsand another to cooperate with the wheels, the raising ofa substantialnumber of needles above limiting positions normally defined by the guardcams.

It is another object of the invention to facilitate the removal ofneedles from the cylinder at any cam section of a machine of thedescribed type.

It is still another object of the invention to have the guard cams in amachine of the described type, retractable from a normal operativeposition in which they limit the upward movement of needles over theraise and placer cams to a retracted position wherein the needles may bepulled above such normally defined limiting positions.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing the camside ofa cam section block constructed according to the invention,

FIG. 2 is a fragmentary perspective view showing the cams of FIG. I andcooperating knitting needles,

FIG. 3 is a perspective view showing the other side of the section blockof FIGS. I and 2,

FIG. 4 is a side view of the cam section block of FIG. 1 taken with thepattern wheel removed,

FIG. 5 is a face view taken on the cam side of two cam section blocksconstructed in accordance with the invention and arranged as they appearwhen assembled in a machine,

FIG. 6 is a sectional view taken on the plane of the line 6-6 of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings,reference character I0 designates a cam section block for a circularknitting machine such as described in copending U.S. Pat. applicationSer. No. 670,097. As shown such cam section block includes a raise camI2, placer cam 14 and stitch cam I6 which cooperate with the lower buttsI8 of two butt needles 20, the needles being vertically slidable in aneedle carrying cylinder 22. A guard cam 24 is provided over the raiseand placer cams and a wing cam 25 is provided under the stitch cam 16All of the cams are located on one side of the section block, as shown,such side being the radially inward side when the block is mounted on amachine, and means hereinafter described are provided on the radiallyoutward side for moving the guard cam in a radially outward direction. Apattern wheel 26 mounted on a fork 28, which is secured to the block at30 and 32, cooperates with the upper butt 34 of the two-butt needles.The pattern wheel 26 which is rotatable in a plane parallel to the planeof fork 28 includes slots 36 skewed with respect to the plane of patternwheel rotation; and the skewing and rotating planes are so chosen thatthe slots may fully intermesh with the needles 20 when such slots arevertically disposed and ad jacent the needle carrying cylinder 22. Eachpattern wheel slot may as is conventional be filled with a high jack 38,or with a low jack 40, or with no jack depending upon whether it isdesired to raise a needle to knit, tuck or welt knitting height.

Needles 20 move relative to the cam section block in the directionindicated and are raised by cam I2 acting on the butts 18 of theneedles. The pattern wheel slots successively mesh with the raisedneedles rolling into the upper butts 34, and jacks where provided engagethe upper butts 34 to position the needles in a well known manner.

After pattern wheel selection of the respective needles, such needlestravel laterally to engage and be lowered by stitch cam 16 or wing cam25. Needles raised to knit or tuck positions by pattern wheel jacksengage and are lowered by stitch cam 16, and needles not raised by jacksengage wing cam 25 and are lowered to welt height. The wing cam 25 iscompressible into the section block I0, in a well known manner, toprevent damage to the butts of any needles which may have beenimproperly raised as by the pattern wheel.

Placer cam 14 which is cradled in a U-shaped cutout 42 in cam sectionblock I0 is manually positionable to wipe out all tuck and welt patternwheel selections or to wipe out all welt pattern wheel selections. Thepositioning of cam I4, though not shown, may be by means ofa pinion andratchet, as is conventional, the pinion being on axis 44 and the ratchetbeing on the cam I4.

The guard cam 24 includes a portion 46 which is over the raise cam l2and which has a cam surface 48 for limiting the uncontrolled upwardflight of a needle from the raise cam 12 by engagement with their lowerbutts I8. Another portion 50 of the guard cam 24 extends over the placercam 14 and to the stitch cam 16. Such portion 50 of the guard camincludes cam surface 52 having a raise angle about equal to the raiseangle of the raise cam 12, and cam surface 54 which is horizontal. Thecam surfaces 52 and 54 are for limiting, by engagement with lowerneedled butts, the position to which an occasional needle may rise duefor example to its upper butt riding out of a pattern wheel slot, andfor guiding any needle attaining such limiting position into the stitchcam I6.

In accordance with the invention the whole guard cam 24 is renderedmovable between a normal position in which the cam surfaces 48, 52 and54 define limiting positions for the needles as indicated and aretracted position (shown in dotted lines in H6. 4) wherein the needlesmay be raised above such cam surface. As shown, the guard cam 24 isintegral with a boss 56 which is formed on one end of a shaft 58 that isslidable within a cylindrical through opening in cam section block 10.The shaft 58 and cam 24 are biased by a spring 60 to the normal positionof said cam, however, the shaft 58 and cam 24 may be moved to aretracted position by pulling on knob 62 which is slidably mounted on aportion of the shaft 58 extending beyond the outer face 61 of sectionblock 10. A flange 65 on the cam 24 is slidable under fork 28 andprevents any angular movement of the cam. The knob 62 which normallybears against section block at 63 is prevented from sliding off the endof the shaft 58 by a spring washer 64 mounted in shaft groove 66, whichspring washer 64 bears against washers 68 that in turn engage surface 70on the knob 62.

With the guard cam 24 retractable it is possible to raise a substantialnumber of needles at the cam section block to positions in which theirupper butts 34 are well above the pattern wheel and the wheel under suchupper butts can be easily viewed enabling an operator to easily alignthe timing slot of the pattern wheel with the starting needle when amachine is being set up. Heretofore, with cam sections having fixedguard cams but otherwise constructed as described, and closely nested asin FIG. 5 (showing cam section A and B) to provide for a maximum numberof cam sections about a machine, damaged needles could not be withdrawnfrom the needle carrying cylinder and replaced without one or more camsection blocks being first removed. However, with the guard camretractable damaged needles can be completely withdrawn from the needlecarrying cylinder throughout the circumferential distance spanned by theplacer cam and new needles inserted.

While the invention has been described in its preferred form it is to beunderstood that the words used are words of descrip tion rather than oflimitation, and that changes within the purview of the appended claimsmay be made without departing from the true scope and spirit of theinvention.

Having thus set forth the nature of this invention what is claimedherein is:

lclaim:

1. in a pattern wheel feed station of a circular independent needleknitting machine including multibutt needles and having tandemlydisposed in the direction of relative needle travel, a raise camengageable with a first butt of the multibutt needles, a pattern wheelfollowing the raise cam adapted to raise selected ones of the needles bya second butt to predetermined heights, and a stitch cam following thepattern wheel, the improvement comprising:

a. a movable guard cam having a normal operative position in which thefirst needle butts may engage one portion of the cam to prevent theuncontrolled flight of needles from the raise cam and in which the firstneedle butts may engage another portion of the cam limiting the verticalpositions attainable by needles when located between the raise andstitch cams, and

b. means for moving the guard cam in a generally radial direction andaway from the needles so that the guard cam may be positioned to permitthe multibutt needles to be raised without the first butts engaging saidguard cam.

2. The combination as defined in claim 1 including a placer cam locatedunder said another portion of the guard cam.

3. The combination as defined in claim 1 wherein said guard cam isspring biased in a direction which is generally radially inward on themachine.

4. The combination of claim 1 including a cam section block having allof the cams located on the radially inward side, and means on theradially outward side for moving the guard cam in a radially outwarddirection.

5. The combination of claim 4 wherein the guard cam is mounted on ashaft which is radially slidable in said cam section block.

1. In a pattern wheel feed station of a circular independent needleknitting machine including multibutt needles and having tandemlydisposed in the direction of relative needle travel, a raise camengageable with a first butt of the multibutt needles, a pattern wheelfollowing the raise cam adapted to raise selected ones of the needles bya second butt to predetermined heights, and a stitch cam following thepattern wheel, the improvement comprising: a. a movable guard cam havinga normal operative position in which the first needle butts may engageone portion of the cam to prevent the uncontrolled flight of needlesfrom the raise cam and in which the first needle butts may engageanother portion of the cam limiting the veRtical positions attainable byneedles when located between the raise and stitch cams, and b. means formoving the guard cam in a generally radial direction and away from theneedles so that the guard cam may be positioned to permit the multibuttneedles to be raised without the first butts engaging said guard cam. 2.The combination as defined in claim 1 including a placer cam locatedunder said another portion of the guard cam.
 3. The combination asdefined in claim 1 wherein said guard cam is spring biased in adirection which is generally radially inward on the machine.
 4. Thecombination of claim 1 including a cam section block having all of thecams located on the radially inward side, and means on the radiallyoutward side for moving the guard cam in a radially outward direction.5. The combination of claim 4 wherein the guard cam is mounted on ashaft which is radially slidable in said cam section block.